Do I have to create a new Ubisoft account every time I buy a Ubisoft title?
No. If you have a Ubisoft account and an Xbox Live gamertag, after the first time you create and link your accounts, Ubisoft will automatically save this information for all future Xbox 360 Ubisoft releases. Once you’ve linked your Ubisoft account with your Xbox Live gamertag, you won’t have to ever re-link again, but you will always have to log in to access the exclusive content.